In electrochemical energy storage systems which employ chlorine and/or hydrochloric acid as the chemical components, gas impurities such as carbon dioxide and oxygen evolve from the electrodes and mix with chlorine gas. Additionally, impurities such as iron, manganese, titanium, vanadium and many other metallic and non-metallic impurities leach out of the electrodes and structural components into the electrolyte. When the level of impurities reaches a given degree, the performance of the electrochemical system is adversely affected and if the impurities cannot be economically removed, the contaminated chlorine and the contaminated electrolyte must be replaced. The cost of this replacement can be a considerable burden on the overall economic operation of an electrochemical energy storage system or, indeed, any other process which depends upon high purity chlorine and/or high purity hydrochloric acid. The present methods of transferring and purifying chlorine and hydrochloric acid are cumbersome and expensive.
It is accordingly the object of this invention to provide a facile, inexpensive and simple method and apparatus for the transfer and purification of halogen and/or hydrohalic acid in conjunction with electrochemical energy storage systems which employ halogen and/or hydrohalic acid as chemical components. This and other objects of the invention will become apparent to those skilled in the art from the following detailed description.